Patent GB-636675-A (GB)
Title: Improvements in shaker conveyors
IPC: B65G65/00
Filed: 1946-10-02
Abstract: 636,675. Shaker conveyer. DEHN, S. G. (Goodman Manufacturing Co.). Oct. 2, 1946, No. 29380. [Class 78 (i)] A feeding mechanism for a shaker conveyer comprises :-a reciprocating trough 10 (Fig. 2) which co-operates with a second trough 11 extensible relative thereto ; friction grip elements 17 which are for effecting the relative movement and which are mounted on a carrier 19 ; links 57, and 31 directly connecting theends of carrier 19 with the reciprocating trough and being rectilinearly movable with respect to said trough ; a cam 49 which engages link 31 turns the link with the reciprocating trough in the forward direction ; a cam 55 which engages link 57 and moves it with the reciprocating trough in the backward direction so that the extensible trough is extended or retracted relative to or reciprocated with the reciprocating trough. Figs. 2, 3. Feeding trough 11 has sides 12 which pass loosely between the shoes 13 and rollers 14, which latter are all mounted on rearward-positioned shaker trough 10 so that the latter trough slidingly supports the former trough. The object is to convert the reciprocating movement of the shaker trough 10 and transform it into a rectilinear movement of the feeder trough 11, this latter movement being an extension (or retraction) of the feeder trough towards the coal face. Thus the feeder trough is gripped and extended by friction blocks 17 (the system of levers being duplicated on the other side of the troughs as shown in Fig. 1) which are carried by carrier member 19, and these friction blocks are moved backwards or forwards and also caused to grip or release the feeder trough by the movement of shaft 31 and of link 57, which in turn derive their movement from holding cams 55, 49 which are carried by shaft 50 journalled to the reciprocating trough 10. Carrier member 19 has a pin 32 which slides on shaft 31 and, when this pin 32 is moved forward (to the left in the drawings) by the pressure from one of the cams on shaft 50 the pressure being transmitted via shaft 31, cup 39, spring 37 and sleeve 35 to the pin, the friction blocks 17 are caused to grip the feeder trough on the forward movement 'and release it on the backward movement. Shaft 31 has two cams formed on its right-hand end which are shown as 47 and 51 (Fig. 3). Link 57 (Fig. 8) has two cams formed at its righthand end which are shown as 73 and 67 and is slidingly mounted on block 56 on shaft 50 and pressed therefrom by spring 63 so as to cause the friction blocks to grip on the backward movement and to release them on the forward movement. Holding cams 55, 49 (Figs. 7, 8, 9, 10A, 11A). These are both freely journalled on shaft 50. Holding cam 49 has one surface which engages with cam 47 of shaft 31, and a second surface which engages with cam 73 of links 57. Holding cam 55 has surface 53 which engages with cam 51 on shaft 31 and a second surface which engages cam 67 on link 57. Both holding cams therefore transmit movement to link 57 and to shaft 31. Each holding cam also has a compression spring pivoted to it, i.e. springs 59 and 70 pivoted to holding cams 49 and 55 respectively, (Fig. 2) so that one holding cam is urged clockwise and the other anticlockwise. Each holding cam derives its rectilinear movement from that of shaft 50 so that each such cam reciprocates with the reciprocating trough. Each such holding cam however receives its rotary movement and therefore its angular displacement from the displacement of control handle 85 because the latter is fixed on to shaft 50 and the latter shaft has fixed on it engaging members 75, 76 ; on member 75 is cam 80 which engages a surface 60 on holding cam 49, and on member 76 is cam 84 which engages surface 7L on holding cam 55 ; and thus when handle 85 is moved the two holding cams are angularly displaced. Method of operation (Figs. 4, 5, 6). With trough 10 reciprocating and trough 11 stationary, to extend the trough 11 forwards handle 85 is moved forwards to the left (Fig. 6). This moves engaging member 75 away from holding cam 49 and allows spring 59 to press the holding cam into engagement with the cam 47 of shaft 31 and thus to urge forwards the latter during a forward stroke of'the reciprocating trough. Also holding cam 55 is moved so that its face 53 engages with cam 51 of the same shaft so that in the return stroke shaft 31 is pulled backwards in its bearings. During both these movements link 57 is free to slide over its block 56 on the shaft 50. Thus on one stroke the shaft 31 squeezes the friction grips and moves forward the feeder trough ; on the other stroke, the shaft 31 releases the friction grips which therefore move backwards without engagement and the feeder trough remains in its forward position. The feeder trough is thus gradually urged forward whilst handle 85 remains in this position. To retract the feeder trough 11 control lever 85 is moved over to the right (Fig. 5). Holding cam 49 is moved by its engaging member 75 out of contact with the cam 47 of shaft 31 and into contact with cam 73 of link 57. Holding cam 55 is released to move under the influence of its spring 70 and engages cam 67 of link 57. Shaft 31 has now freedom of movement in its bearings. Holding cam 49 thus moves the link 57 forwards (through cam 73) and holding cams 55 move the link backwards (through cam 67). In these conditions the friction grips grip the feeder trough on the reverse stroke and release it on the forward stroke and the feeder trough is moved gradually backwards towards the reciprocating trough. To couple the feeder trough with the reciprocating trough so that both reciprocate together control handle 85 is moved to the central position (Fig. 4). Holding cam 49 is released from link 57 and moves under its spring 59 to engage cam 47 of shaft 31. Holding cam 55 is already in engagement with cam 67 of link 57. Holding cam 49 moves shaft 31 forward and holding cam 55 moves link 57 backwards and in these conditions the friction grips operate on each stroke.